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101.
Objective:To determine the efficacy of a five-week core stability training program for collegiate athletes on upper extremity performance measures.Methods:Seventy healthy collegiate athletes (age 21.6±1.7years; height 175±4.63 cm; body mass 65.31±5.63 kg) were randomly allocated to experimental (n=35) and control group (n=35). The experimental group has undergone a five-week core stabilisation protocol (three days /week) and regular training, whereas the control group maintained their regular training. The upper quarter Y balance test (UQ-YBT) and Functional throwing performance index (FTPI) were assessed pre and post-training.Results:The results of mixed ANOVA show that there was a significant interaction between time and group variables on YBT (p<0.001, ηp2 =0.759) and FTPI (p<0.001, ηp2 =0.411) after five weeks of core stability training. Statistically, significant improvement was shown in YBT (mean change=15.2, p<0.001) and FTPI (mean change=14.4, p<0.001) in the experimental group; however, there was no significant change observed in both outcomes in the control groups.Conclusion:After five weeks of core stabilisation training program, the measures of UQ-YBT and FTPI were improved, thus advocating the use of a core stabilisation training program among collegiate athletes to enhance their upper extremity performance.  相似文献   
102.
103.
Treatment of systemic fungal infections is difficult because of the limited number of antimycotic drugs available. Thus, there is an immediate need for simple and innovative systems to assay the contribution of individual genes to fungal pathogenesis. We have developed a pathogenesis assay using Caenorhabditis elegans, an established model host, with Saccharomyces cerevisiae as the invading fungus. We have found that yeast infects nematodes, causing disease and death. Our data indicate that the host produces reactive oxygen species (ROS) in response to fungal infection. Yeast mutants sod1Δ and yap1Δ, which cannot withstand ROS, fail to cause disease, except in bli-3 worms, which carry a mutation in a dual oxidase gene. Chemical inhibition of the NADPH oxidase activity abolishes ROS production in worms exposed to yeast. This pathogenesis assay is useful for conducting systematic, whole-genome screens to identify fungal virulence factors as alternative targets for drug development and exploration of host responses to fungal infections.Nosocomial microbial infections are a growing health problem. Among these, fungal infections are especially threatening, with an estimated mortality rate of 40% (47). The key reason for this alarming mortality rate is the limited range of antifungal agents. Identification of new drug targets requires high-throughput infection assays that are complicated by the very fact that they involve two organisms: a host and a pathogen.We have taken a reductionistic approach to studying host-pathogen interactions and have developed a Saccharomyces cerevisiae-based assay to understand the genetic and molecular mechanisms of fungal pathogenesis. Using Caenorhabditis elegans as a model host, we have found that S. cerevisiae infects the worm, producing visible disease phenotypes. The two organisms used in our study are specifically suited for host-pathogen infection studies because both genomic sequences have been completely determined and mutants are readily available. A complete genome knockout collection is available for S. cerevisiae, a resource that does not exist for any fungal pathogen. Likewise an RNA interference (RNAi)-mediated knockdown genomic library is available for C. elegans. These unique tools are key in the context of a genetic screen and allow us to systematically scan the entire genomes to identify fungal virulence factors and modulators of host immunity that combat a fungal pathogen.The budding yeast S. cerevisiae has recently been described as an emerging pathogen and has been isolated from human patients (34, 35). It is routinely used as a model for pathogenic fungi because a large proportion of its genes are conserved in pathogenic fungi (for a review, see reference 32). Homologs of genes and pathways identified in S. cerevisiae have been shown to be important in bona fide pathogens. It has also been used for the identification of gene products important for fungal survival in the mammalian host environment (21, 46). For example, the SSD1 allele type affects pathogenicity of yeast, indicating that allelic variation at the SSD1 locus may be important for survival under various conditions (46). This has allowed investigators to use reverse genetic approaches to study contributions of genes whose importance has been established in S. cerevisiae.Caenorhabditis elegans has emerged as a valuable model host in which to study pathogenesis and innate immunity (for a review, see reference 22). Microbial genes essential for virulence in mammalian models have been shown to be required for pathogenicity in nematodes (43). These studies have primarily explored bacterial species and have tested only a few fungi, such as Cryptococcus neoformans and Candida albicans, to explore virulence strategies. These studies focus on a killing assay using C. elegans and have identified several virulence factors with homologs in S. cerevisiae (4, 37), suggesting that genes and pathways we have identified in S. cerevisiae are likely to be found in pathogens. Moreover, other pathogenic fungi tested are limited in the repertoire of laboratory tools available for their study, making them recalcitrant to genetic manipulation and inappropriate for whole-genome high-throughput approaches to studying fungal virulence. Recently, Breger et al. described the application of a C. elegans-based infection assay as a tool to screen a chemical library for candidate antifungal compounds (9). Our investigation complements these studies in two significant ways. First, it allows us to identify genes that exacerbate as well as attenuate the pathogenic process, because we use an intermediate disease phenotype, while most other studies have used death as an end point phenotype. This aspect, taken together with the fact that S. cerevisiae shares significant genetic identity with pathogenic fungi, suggests that our study will yield a basic understanding of fungal pathogenesis. Second, it allows us to conduct a systematic, unbiased, whole-genome screen, which is currently not available for pathogenic fungi. Furthermore, genes and pathways identified may be targeted for antimycotic drug development.Facets of innate immunity are evolutionarily conserved from nematodes to mammals. For example, a common defense strategy of mammals (phagocytes), (14), plants (3), and insects (23) is to produce reactive oxygen species (ROS), which directly damage pathogens. In human phagocytes, an NADPH oxidase enzyme complex produces ROS in host defense (19, 41). In Drosophila melanogaster, ROS are generated in the intestine by a NADPH oxidase to combat ingested bacteria (23). Loss of NADPH oxidase activity makes the fly susceptible to the bacterial infection (23, 24). Likewise, C. elegans has also been shown to produce ROS, such as superoxide and/or hydrogen peroxide, when it ingests bacterial pathogens (12). In each case, pathogen death can be abrogated by the addition of enzymes such as catalase that break down ROS (8, 27, 36), suggesting that ROS production plays a key role in a variety of pathogenic interactions.We have found that S. cerevisiae can cause infection and death in C. elegans. Our data indicate that the nematode host produces ROS in response to fungal infection. We demonstrate that mutant yeast carrying deletions of genes that mediate oxidative stress responses fail to induce the Dar disease phenotype except in mutant worms with an altered dual oxidase gene, suggesting that the generation of ROS is a part of the defense strategy for the host and the neutralization of ROS is needed for persistent fungal infection.  相似文献   
104.
Protein function is intimately related to the dynamics of the protein as well as to the dynamics of the solvent shell around the protein. Although it has been argued extensively that protein dynamics is slaved to solvent dynamics, experimental support for this hypothesis is scanty. In this study, measurements of fluorescence anisotropy decay kinetics have been used to determine the motional dynamics of the fluorophore acrylodan linked to several locations in a small protein barstar in its various structural forms, including the native and unfolded states as well as the acid and protofibril forms. Fluorescence upconversion and streak camera measurements have been used to determine the solvation dynamics around the fluorophore. Both the motional dynamics and solvent dynamics were found to be dependent upon the location of the probe as well as on the structural form of the protein. While the (internal) motional dynamics of the fluorophore occur in the 0.1-3 ns time domain, the observed mean solvent relaxation times are in the range of 20-300 ps. A strong positive correlation between these two dynamical modes was found in spite of the significant difference in their time scales. This observed correlation is a strong indicator of the coupling between solvent dynamics and the dynamics in the protein.  相似文献   
105.

Background

The ciliary body is the circumferential muscular tissue located just behind the iris in the anterior chamber of the eye. It plays a pivotal role in the production of aqueous humor, maintenance of the lens zonules and accommodation by changing the shape of the crystalline lens. The ciliary body is the major target of drugs against glaucoma as its inhibition leads to a drop in intraocular pressure. A molecular study of the ciliary body could provide a better understanding about the pathophysiological processes that occur in glaucoma. Thus far, no large-scale proteomic investigation has been reported for the human ciliary body.

Results

In this study, we have carried out an in-depth LC-MS/MS-based proteomic analysis of normal human ciliary body and have identified 2,815 proteins. We identified a number of proteins that were previously not described in the ciliary body including importin 5 (IPO5), atlastin-2 (ATL2), B-cell receptor associated protein 29 (BCAP29), basigin (BSG), calpain-1 (CAPN1), copine 6 (CPNE6), fibulin 1 (FBLN1) and galectin 1 (LGALS1). We compared the plasma proteome with the ciliary body proteome and found that the large majority of proteins in the ciliary body were also detectable in the plasma while 896 proteins were unique to the ciliary body. We also classified proteins using pathway enrichment analysis and found most of proteins associated with ubiquitin pathway, EIF2 signaling, glycolysis and gluconeogenesis.

Conclusions

More than 95% of the identified proteins have not been previously described in the ciliary body proteome. This is the largest catalogue of proteins reported thus far in the ciliary body that should provide new insights into our understanding of the factors involved in maintaining the secretion of aqueous humor. The identification of these proteins will aid in understanding various eye diseases of the anterior segment such as glaucoma and presbyopia.  相似文献   
106.

Background

Optimum efficiency of the folate pathway is considered essential for adequate ovarian function. 677 C>T substitution in the 5, 10-methylene tertrahydrofolatereductase (MTHFR) gene compromises activity of the MTHFR enzyme by about 50%. The significance of correlation between 677C>T substitution and PCOS remains dubious due to the low power of published studies.

Methods and Results

We analyzed MTHFR 677 C>T site in ethnically two different PCOS case-control groups (total 261 cases and 256 controls) from India. The data analysis revealed a lack of association between this polymorphism and PCOS [OR = 1.11 (95%CI = 0.71–1.72), P = 0.66]. Group-wise analysis on the basis of ethnicity also revealed no association in any of the ethnic groups [Indo-Europeans, P = 1; Dravidians, P = 0.70]. Homocysteine levels did not differ significantly between cases (15.51 μmol/L, SD = 2.89) and controls (15.89 μmol/L, SD = 2.23). We also undertook a meta-analysis on 960 cases and 1028 controls, which suggested a significant association of the substitution with PCOS in the dominant model of analysis (OR = 1.47 (95%CI = 1.04–2.09), P = 0.032]. Trial sequential analysis corroborated findings of the traditional meta-analysis. However, we found that the conclusions of meta-analysis were strongly influenced by studies that deviated from the Hardy Weinberg equilibrium. A careful investigation of each study and a trial sequential analysis suggested that 677 C>T substitution holds no clinical significance in PCOS in most of the populations.

Conclusion

In conclusion, MTHFR 677 C>T polymorphism does not affect PCOS risk in India. The association seen in the meta-analysis is due to an outlier study and studies showing deviation from the Hardy Weinberg equilibrium.  相似文献   
107.
We have developed an efficient transformation system for Tylophora indica, an important medicinal plant in India, using Agrobacterium rhizogenes strains LBA9402 and A4 to infect excised leaf and stem explants and intact shoots at different sites. The induction of callus and transformed roots was dependent on the bacterial strain, explant type and inoculation site used. Transformed roots were induced only in explants infected with A. rhizogenes strain A4, while an optimal transformation frequency of up to 60% was obtained with intact shoots inoculated at the nodes. The presence of the left-hand transferred DNA (TL-DNA) in the genome of T. indica roots induced by A. rhizogenes was confirmed by PCR amplification of the rooting locus genes of A. rhizogenes. Root growth and the production of tylophorine, the major alkaloid of the plant, varied substantially among the nine root clones studied. Both parameters increased over time in liquid cultures, with maximum biomass and tylophorine accumulation occurring within 4–6 weeks of growth in fresh medium. Interestingly, in liquid culture, the culture medium also accumulated tylophorine up to concentrations of 9.78±0.21 mg l–1.  相似文献   
108.
Arsenic (As) is a potential contaminant of groundwater as well as soil in many parts of the world. The effects of increasing concentration of As (25 μm and 50 μm As2O3) in the medium on the content of starch and sugars and activity levels of enzymes involved in starch and sugar metabolism i.e. α-amylase, β-amylase, starch phosphorylase and acid invertase were studied in germinating seeds of two rice cvs. Malviya-36 and Pant-12 during 0–120 h period. As toxicity in situ led to a marked decline in the activities of α-amylase, β-amylase in endosperms as well as embryoaxes of germinating rice seeds. The activity of acid invertase increased in endosperms as well as embryoaxes whereas starch phosphorylase activity declined in endosperms but increased in embryoaxes under As treatment. In endosperms a decline in starch mobilization was observed under As toxicity, however under similar conditions the content of total soluble sugars increased in embryoaxes. The observed inhibition in activities of amylolytic enzymes might contribute to delayed mobilization of endospermic starch which could affect germination of seeds in As polluted environment, while the induced acid invertase activity and increased sugar accumulation in embryoaxes could serve as a possible component for adaptation mechanism of rice seedlings grown under As containing medium.  相似文献   
109.
Despite growing scientific, public and regulatory concern over the discharge of radioactive substances, no serious attempts have been made to develop a rationale to evaluate the impact of environmentally relevant radionuclides in the aquatic environment. In this study, we have evaluated the genotoxic effects and tissue-specific concentration of tritium (added as tritiated water, HTO) in the adult life stage of the edible mussel, Mytilus edulis. The genotoxic effects were quantified in terms of the induction of: (a) micronuclei (MN), and (b) DNA single-strand breaks/alkali-labile sites using alkaline single-cell gel electrophoresis (Comet assay) in the haemocytes of exposed animals. The assays were optimised and validated using a range of concentrations (18-56 mgl(-1)) of ethylmethane sulfonate (EMS), a direct-acting reference genotoxic agent, over different exposure periods. Mussels were exposed to a series of concentrations of HTO equivalent to a dose range from 12 to 485 muGyh(-1) for 96 h, and different tissues and organs were then extracted and analysed. The study revealed a dose-dependent increase in the response for both the MN test and the Comet assay and for both EMS and HTO. In addition, HTO delivering dose rates below 500 muGyh(-1) was shown to be capable of inducing genetic damage in the haemocytes of these bivalves. The study also showed that inorganic tritium accumulated differentially in mussel tissues in a dose-dependent manner, with the gut accumulating the highest amount of radioactivity, followed by the gill, mantle, muscle, foot and byssus thread. The faeces and pseudo-faeces accumulated least radioactivity over the exposure period. Differential accumulation of radionuclides has significant implications for biomonitoring programmes, for this and other aquatic organisms. The study also suggests that the generic dose limits recommended by the International Atomic Energy Agency for the protection of aquatic biota might not be applicable to all aquatic organisms.  相似文献   
110.
Composite polymer membrane of polyvinyl alcohol (PVA) and acrylamide was prepared on cheesecloth support by gamma-irradiation induced free radical polymerization. The enzyme urease was entrapped in the membrane during polymerization and was cross-linked within the matrix using glutaraldehyde. The membranes could be reused a number of times without significant loss of urease activity.  相似文献   
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